Stove-pipe damper



(No Model.) 2 Sheets-Sheet 1.

L. M. DEVORE.

STOVB PIPE DAMPER.

- No. 409,459. Patented Aug. 29, 1999.

H Ill u |n|||||| lulmmummu (No Model.) 2 sheets-sheen 2.

L. M. DEVORE.

STGVE PIPE DAMPBR.

No. 409,459. Patented Aug. 20, 1889.

0 l 'JY AUNITED STATES PATENT Orricn.

LEVI M. DEVORE, OF FREEPORT, ILLINOIS.

STOVE-PIPE DAM PER.

SPECIFICATION forming part of Letters Patent No. 409,459, dated August 20, 1889.

Application filed February 23, 1889. Serial No. 300,799. (No model.)

To all whom t may concern,.-

Be it known that I, LEVI M. DEVORE, a resi dent of Freeport, in the county of Stephenson and State of Illinois, have invented certain new and useful Improvements in Stove- Pipe Dampers; and I do hereby declare the following to be afull, clear, and exact description of the invention, such as will enable others skilled in the art to which it pertains to make and use the same.

My invention relates to improvements in stove-pipe dampers,` and is fully described and explained in this specification and shown in the accompanying drawings, in which- Figure lis a plan of one form of my improved damperin operative position in a pipe. Fig. 2 is a plan of a modified form of the damper, showing the connection of the blade and handle. Fig. 3 is a section through the line X X, Fig. l. Figs. 4., 5, and 6 are sections through the lines Y YZ Z M M, Fig. 2, respectively. Fig. 7 is a plan of al second modified form of the damper.

In Figs. 1 and 3, A is a dampenblade formed with a central opening A', and provided at one point in its periphery with a preferably pointed gudgeon B and at a diametricallyopposite point with a boss B', the boss and gudgeon being both formed integrally with the blade. From the center of the boss B projects a handle C, also formed in one piece with the boss and blade, and curved to form a crank for t-urning the blade on its axis when the gudgeon and the portion of the 4handle next the boss are journaled in a pipe, as shown in Fig. l. A spring D encircles the handle C and abuts at its inner end against the pipe when the damper is in working position, the outer end of the spring being' abutted against a suitable projection c on the handle C, situated, preferably, at the end thereof. The spring has a normal length greater than the distance between the proj ection c and the surface of the pipe and is compressed when in position on the handle. It therefore exerts a force which tends to push the projection c away from the pipe, and thus toidraw the boss B against the inner face of the pipe and produce a friction which prevents accidental displacement of the damperwhen turned to any desired position.

i The projection c is preferably formed integrally on the handle, and in order thatit may Aspiral groove g, adapted to permit the spring to be passed over it by spiral movement, like that of a screw. Ihave also found it advisa ble to make the inner end of the spring of greater diam eter than the outer, in order that all but the extreme outer end of the spring may be passed directly over the projection c, leaving only the outermost coils to be passed over it by a twisting or screw movement. If the spring be sufficiently reduced in diameter at its outer end, the end of the handle need not be provided with an enlargement, but the groove may be formed in the handle and the small coils screwed into the groove, where they will be securelyheld. As the crank throws the damper slightly out of balance, I have restored the balance by forming on the blade a counter-weight A situated on the opposite half of the blade from that toward which the handle is turned.

Figs. 2, 4, 5, and 6 illustrate a form of damper just the same as that shown in Figs. l and 2, except that the handle is formed on a separate piece from the blade. In this form the handle C has a shank C', provided at its inn ner end with lugs C. These lugs may be passed through an opening a in the blade and dropped through a second opening a, and then slightly retracted to the position shown in Fig. 2. Then the parts are thus connected, the device is practically the same as the one-piece form shown in Figs. l and In this form I have counterbalanced the handle by forming the opening A at one side of the center, thus lightening the side of thc blade toward which the handle is turned.

Either one of the dampers above described may be applied to a pipe by inserting the blade and handle in the pipe, passing the handle through a suitable hole in the pipe at one point and the gudgeon through an opposite hole. The spring may then be applied, and the damper is ready for use. When either of these forms is in operative position, the spring C not only produces necessary friction, but also forms a non-heating cover for the handle, so that the damper may be operated at any time without danger of burning the hand of the operator.

It is not essential that the handle be bent wholly to one side of the axis ot the blade7 as 'spring or as to the operation and management of the damper.

Having now explained my in vent-ion and its operation,what I claim as new, and desire to secure by Letters Patent, is-

l. The combination of a damper-blade, a rigid handle adapted to operate the same and formed with a spiral groove, and a spiral spring adapted to be passed over said handle by moving one or more of its coils spil-ally along said groove.

2. The combination, with a damper-blade and a curved handle rigid therewith and adapted to be passed through an opening in the pipe, of a spring encircling the handle and abutting against the pipe and against a proj ection or enlargement on the handle, the projection or enlargement being formed with a spiral groove adapted to permit the passage of the spring over it by a spiral movement.

3. The combination, with the blade A, having the gndgeon B, the boss B', and curved handle C, of the spiral spring D, adapted t0 abut at one end against a pipe in which the damper is placed and at the other against an enlargement c on the handle C, substantially as and for the purpose set forth.

In testimony whereof I have signed this specification in the presence of two subscrib ing witnesses.

LEVI M. DEVORE.

Witnesses:

R. I-I. WILEs, J. A. GRAIN. 

